In one type of strain relief known in the prior art, a rubber or plastic grommet is inserted and secured into an aperture in a partition or wall through which at least one wire is inserted and then clamped to the partition or wall. Unfortunately, the wire or wires tend to be subjected to crushing and resultant damage caused by clamping. Additionally, the clamp does not conform well to a variety of wire shapes or wire bundle configurations, requiring specialized hardware instead.
Another type of strain relief includes a collar placed over a wire, with a portion or associated part of the collar being crimped to secure the collar onto the wire. The collar is then inserted into the aperture of a partition and secured therein, thereby retaining the wire into and through the aperture.
Other strain reliefs include a collar through which the wire is inserted, held in place by a tight or compressive fit between the collar and wire. As a result, insertion of the wire into and through the collar can damage the wire. Further, it can be difficult to locate the collar along the wire except near an end of the wire due to the forces required to move the collar into position.
Alternatively, the collar initially can be provided with an inner diameter sufficiently large to allow easy positioning and placement of the collar onto the wire. In this case, the collar can thereafter be compressed onto the wire using a clamp or by providing a taper such that the collar is compressed upon insertion of the collar into the aperture. The clamp or aperture, therefore, must have a specific shape and size to provide the necessary compressive forces sufficient to hold the collar onto the wire without damaging the wire. Therefore, this technique does not readily accommodate various wire sizes, shapes, and bundle configurations without the requirement of a modification to the hardware in each situation. Slight variations due to wire irregularities or wire positioning within a bundle or cable could affect strain relief performance.
Because prior art strain reliefs utilize preformed collar and clamps, they are not readily adaptable to varying wire sizes, shapes, and bundle configurations. Further, these strain reliefs can required the wire to be protected to be forcibly inserted into and through a tight fitting, compressive collar prior to insertion through an aperture. The insertion force required to install the strain relief can itself damage the wire. In addition, wires within a conventional strain relief are exposed to environmental contamination.
A need therefore exists to provide a strain relief which can be easily installed and positioned on a wire to be protected without damaging the wire. Further, a need exits for a strain relief which is readily adaptable to various wire sizes, shapes and wire bundle configurations.
Accordingly, one object of the invention is to provide an easily installed and positioned strain relief for at least one wire passing through an aperture in a partition.
Another object of the invention is to provide a strain relief which is adaptable to various wire sizes, shapes and wire bundle configurations.
Still another object of the invention is to provide a strain relief which can be secured onto a wire or wires to be protected without causing damage thereto.
A further object of the invention is to provide a wire strain relief which can be secured into position without pinching underlying wire or wires.
Still another object of the invention is to provide a strain relief which prevents wire movement axially in both directions through an aperture in a partition.
Another object of the invention is to provide a strain relief which accommodates injection of a caulking compound to fill interspaces between and among the wire or wires and the strain relief to provide an environmental barrier.